Precut logs for use in constructing log cabins, lodges, shelters and the like may be made from logs which have been planed and grooved on two opposite sides and debarked on the other two sides or from logs which have been planed and grooved on two opposite sides and planed on the other two opposite sides. In the first instance, the debarking produces nicks, cuts and the like in the side surfaces and one of the objects of the invention is to provide apparatus for removing the blemishes without spoiling the natural contour of the side surfaces and in the second instance, it is desirable to provide apparatus capable of imparting to the side surfaces a surface contour simulating a natural log or to impart to the side surfaces some distinctive surface pattern other than that of a natural log. Other objects are to provide apparatus capable of cutting one or both sides of a log so that, for example, the outer side appears to be a log structure and the inner side is smooth and to provide for making the top surfaces of the log narrower than the bottom surfaces so that, when stacked, the bottom surface of any given log will overhang the top surface of the log immediately therebelow.